1. Field of the Invention
The present invention provides a technical method to create a three-dimensional air sealable packaging material by using a self-adhesive non-reversible air blockage technique (one way valve) and multi-layered functional polyethylene soft plastic resins. This material can be used in areas such as consumer electronics, glassware, high precision instruments and meters, art crafts, printer cartridges and products that are fragile, have high consumer values and require high safety protection performances. The present invention integrates multiple functions such as for direct load resistance, for anti-vibration, for being sealable, for anti-humidity, and for good shock resistance, provides good protective performance and, yet, is considered environmental friendly packaging material. It can be used in product protection, space void filling, and product area protection or used as protective isolator cushions during shipping. Most importantly, it can also be designed as printable and, hence, can be directly used as sales packaging combining with protective performance.
2. Description of the Related Art
Globalization has increased the distance between product manufacturing and the product consumer market, and this trend has pushed the fast development of protective packaging in order to meet long distance protection shipping needs. Traditional Expanded Polystyrene (EPS) and Expanded Polyethylene (EPE) products are only shipped to users after foam molding or processing at the supplier's factory location. The formed, finished, EPS products are large in size and very inconvenient for transportation and storage. On-site foaming materials developed for convenience of transportation mainly use polyurethane foaming plastic materials to expand around the content article and form the protective mould around it. However, it is expensive to use and requires on-site equipment to process. That it also needs skilled workers as well as the working load makes it impossible for application for large scale product lines such as those for electronic products. Most importantly, the drawbacks of the Expandable Polystyrene products have caused many environmental concerns, and it is becoming the “white pollution” of this century. Considering the fact that protective products made of EPS material are used in a very short time span between manufacturing, shipping, and warehousing for commercial sales and finally to the consumer, EPS products are non-recyclable after use, and it is non-degradable lasting for hundreds of years once it is formed. The large volume of EPS packaging wastes has caused tremendous environmental damage. Incineration causes toxic gas to the atmosphere, and sending to a waste land fill will shorten the usage design of the waste land fill because these EPS products can not be decomposed for hundreds of years. With increasing concerns about environmental pollution issues, the development of this foam plastic material is greatly restricted by governmental regulation and public attentions. At the same time, products available to the protective packaging market are all limited by the large space volume needed to ship and to warehouse these packaging material. Shipping costs and warehouse handling costs have limited the sales of these products to within a short sales diameter distance. Hence, the present invention has focused on creating a marketable product that is easy for long distance transportation, on-site rapid formation, and good protective performance and, yet, that is of great benefit to the environment.
With the rapid development of soft plastic material, more and more industries can benefit from the design and functional expendability by utilizing the properties of this material. Traditional air filling packaging generally uses a heat sealing technique to form simple round shape air bubbles (BUBBLE WRAP), blocks or columns. The bubble wrap can be transported in rolls. However, products in other shapes request the installation of complex heat-sealing equipment on site to produce the product. As the protective effects and the transforming shapes of such products are limited, they are often used as padding or for filling space only. At the same time, air cannot be kept inside for a long time due to the unstable heat sealing quality when produced on site. Therefore, the development of packaging products using air as cushioning media has long been limited.
Literature, such as Walker (1981, U.S. Pat. No. 4,191,211) and Koyanagi (1987, U.S. Pat. No. 4,708,167), has recorded the use of valve structures made of soft plastic material such as rubber or latex. This valve material can be used in designs such as water bags, coffee bean bags and balloon toys. This soft plastic valve can provide a passage for air or liquid to enter but prevents the leakage of air and liquid. On the basis of such theory, using different materials may be applicable in different areas such as life-saving jackets and sealed devices to keep liquids in the bladder. In 2005, Fu Jinfang in “Packaging Engineering” and Liu Gong in “Packaging and Food Machinery” published articles on the feasibility study of using air for cushioning, providing the present invention a very good theoretical basis.
China's Patent Application No. 200510025833.4 published in Nov. 22, 2006 demonstrated an air packaging material and its production method by using a self-adhesive, non-reversible, air blockage technique. Such packaging material, comprising 4 layers of plastic films, formed a space for air storage by heat-sealing at specified locations. Air can be preserved in the space in a long-lasting manner utilizing both the self-adhesive film and the function of air pressure. Air and soft plastic film form a functional material that could be designed to have different functions such as shock-resistance, compression-resistance and moisture blockage.
China's Patent Application No. 200580016507.5 published in Nov. 21, 2007 demonstrated an air packaging device structure with improved shock absorption performance for the protection of products inside the container case. The air packaging device was comprised of first and second plastic films adhered by heating at prefabricated locations to produce a number of air chambers. Each air container has a number of serially connected air chambers. A number of one-way valves established at the entrances of the corresponding air containers allowing allow pressurized air to move forward. The air inlet is publicly connected with the one-way valves. Heat-sealing protrusions are formed at the lateral edges of the air packaging device. The prefabricated points of the air container are adhered to the heat-sealing edges. Thus, the open-mouth container part is created, which will wrap the product inside and which has the padding part in support of the container part when the air packaging device is filled with pressurized air.
The air packaging device published by the above Chinese patent applications is as illustrated in FIG. 1. Air, through the main channel 1 and the one-way valve 2, gets into air chambers 3. The air chambers 3 are roughly the same in diameter, and the maximum load bearing is uniformly distributed throughout the surface area. When the packaged object falls, all the air chambers are impacted simultaneously, which is the same as a flat surface. In this case, the pressure that can be withstood is relatively small, and the cushioning effects are not very satisfactory.
On the other hand, after filling with air, the size of the object that can be contained in the internal space is basically defined. If the article is too big in size, it cannot be placed inside the air packaging device. On the contrary, if the article is too small in size, the article may be subject to motion and shock and may pierce the air packaging device, resulting in the failure of the cushioning protection. In case of articles for packaging with slight differences in size (such as 14 inch and 15 inch laptop computers), two sets of production techniques and moulds are required, leading to greater production costs. Meanwhile, increasing packaging volume will increase transportation costs and will greatly increase the costs for end products in the case of globalized purchase, manufacturing, transportation and sales.
The present invention is therefore intended to obviate or at least alleviate the problems encountered in the prior art.